Electric incandescent lamp



lFeb. 13, 1934.

C34 LESSMANN ELECTRIC INCANDES CENT LAM? Filed NOV. 25, 1930 TN VEN TDF.. -D FIFA/ l EESM NN,

FI-FIS TTUANEY Patented Feb. 13, 1934 UNlTED STATES PATENT OFFICE ELECTRIC INCANDESCENT LAMP Application November 26, 1930, Serial No. 498,367, and in Germany February 8, 1930 3 Claims.

My invention relates to electric incandescent the arbor 12, supplies additional supporting means lamps and more particularly to elongated lamps for the lament.

of the decorative type such as candle lamps in which comparatively long leads are necessary as 5 the lament is located in the tip end of the lamp. My invention provides a very secure means of supporting the said leads to prevent short circuits between them and undue vibration of the filament from shock.' According to my invention the leads are Wound around the arbor of the glass stem. In one form the leads are wound in a double helix and both contact with the arbor. In another form, they are wound around said arbor but have an insulating sleeve between them. Other fea tures and advantages of my invention will appear from the following description of species thereof and from the accompanying drawing.

In the drawing, Fig. 1 is a side elevation of the lamp of my invention; and Fig. 2 is a side elevation of a portion of a lamp embodying a modification of my invention.

Referring now to the drawing, and more particularly to Fig. 1, my lamp comprises the glass bulb 10 within which is supported a stem 11, a

glass arbor 12, leading-in wires 13-14 and lament 15. The stem is of the usual tipless construction, disclosed in Mitchell and White Patent 1,423,956, having the exhaust tube 16 and sealed thereinto at the stem press 17, the leading-in wires 13-14. As this lamp is of a type in which the lament 15 is mounted in the tip of the bulb at a considerable distance from the stem press, the leading-in wires are wound around the arbor. As shown, these wires are wound into a double helix and do not touch each other at any point. The support wire 18 projecting from the end of In the modification of my invention shown in Fig. 2, which is embodied in a lamp similar in construction to that shown in Fig. 1, one of the leading-in wires is wound over a sheet of insulating material 19, such as asbestos, which covers the helix formed by the other Wire. This construction prevents all possibility of the leading-in wires touching each other in case the lament should break and the leading-in wires move out of place.

What I claim as new and desire to secure by Letters Patent of the United States, is:

1. In an electric incandescent lamp, the combination of an elongated bulb, a glass stem therein comprising an arbor, a filament, and inner leads extending from said stem and connected to and serving to support said lament, said inner leads having portions thereof wound around said arbor. 'Z5

2. In an electric incandescent lamp, the combination of an elongated bulb, a glass stem therein comprising an arbor, a. lament, and a pair of inner leads extending from said stem and connected toand serving to support said filament, e0 said inner leads having portions thereof wound around said arbor so as to form a double helix.

3. In an electric incandescent lamp, the combination of an elongated bulb, a glass stem therein comprising an arbor, a filament, a pair of inner leads extending from said stem and connected to and serving to support said lament, said inner leads having adjacent portions thereof wound around said arbor, and an insulating sleeve between said portions of said leads. 9o

GOTTFRIED LESSMANN. 

